Circuit ISUZU KB P190 2007 Workshop Repair Manual

7A2-90 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

DTC P0962 or P0963 (Flash Code 35)




RTW 77ALF001501

Circuit Description
The pressure control solenoid is a PW M duty control
solenoid located in the valve body.
The pressure control solenoid is a TCM-controled
device used to regulate transmission throttle pressure
by energizing current from the TCM.
Condition For Running The DTC
All of the following conditions are met.
(1) All of the following conditions are met for 2 seconds or more continuously.
• The supply voltage is more than 10.2 volts and
less than 15.5 volts.
(2) Not emergency mode.
(3) All of the following conditions are met. • Device Control is not operating.
• Disable Normal Communication Service is
receiving enable.
• DTC Clear is not operating.
Condition For Setting The DTC
(1) All of the following conditions are met for 12.5
seconds or more continuously. (DTC P0962)
• 1 second or more passed after ignition short
failure detection condition is met or ignition short
failure is never detected after ignition “ON”.

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-91

• Feedback current value is less than 92 mA
(2)
All of the following conditions are met for 0.5
seconds or more continuously. (DTC P0963)
• 1 second or more passed after open failure
detection condition is met or open failure is not
detected after ignition “ON”.
• Feedback current value is more than 1357 mA.
Action Taken When The DTC Sets
• No squat control.
• No line pressure reduction control at gear change.
• No lock-up control.
• No slope control.
• No torque reduction control.
• No line pressure reduction control at garage.
• Line pressure FULL output.
• No shift solenoid functional failure detection.
• No L-up solenoid functional failure detection.
• No pressure control solenoid Feedback stuck failure detection.
• Check Trans “ON”.
• DTC stored.
• MIL request “ON”. (EURO 4 only)
Conditions For Clearing The DTC
•
The DTC can be cleared from the TCM history by
using a scan tool.
• The DTC will be cleared from history when the vehicle has achieved 40 warm-up cycles without a
failure reported.
•
After more than 1 second has elapsed after the
ignition key has been turned “ON”, short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.
Diagnostic Aids
• Inspect the wiring for poor electrical connection at the TCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring.
Inspect for a broken wire inside the insulation.
• W hen diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.
Circuit/System Testing DTC P0962 or P0963

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Turn “ON” the ignition.
3. Record scan tool data.
4. Operate the vehicle within scan tool data.

Does a scan tool indicate DTC P0962 or P0963? — Go to
Step 3 Refer to
Diagnostic Aids
3 Measure the resistance of pressure control solenoid.
1. Turn “OFF” the ignition.
2. Disconnect the automatic transmission connector.
3. Measure the resistance between automatic
transmission terminal E54-2 and automatic
transmission terminal E54-6.

Is the resistance specified value? 5 to 5.6Ω at
20 °C (68 °F) Go to
Step 4 Go to Step 7

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-93

DTC P0973 or P0974 (Flash Code 31)




RTW 77ALF001501

Circuit Description
The shift solenoid S1 changes the hydraulic route with
the signals from the TCM according to the vehicle
speed and the throttle opening to control shifting. W hen
the shift solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.
Condition For Running The DTC
All of the following conditions are met.
(1)
All of the following conditions are met for 2
seconds or more continuously.
• The supply voltage is more than 10.2 volts and
less than 15.5 volts.
(2) Not emergency mode.
(3) 0.025 seconds or more passed after the state o
f
power “ON” solenoid is changed.
(4) All of the following conditions are met. • Device Control is not operating.
• Disable Normal Communication is receiving
enable.
• DTC Clear is not operating.


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ISUZU KB P190 2007

7A2-94 TRANSMISSION CONTROL SYSTEM (AW30–40LE)


Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P0973)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P0974)
Action Taken When The DTC Sets
• No L-up control.
• No line pressure reduction control at gear change.
• No torque reduction control.
• No squat control.
• No slope control.
• No line pressure reduction control at garage.
• No input revolution sensor failure detection.
• No shift solenoid failure detection.
• No L-up solenoid failure detection.
• Change to emergency mode.
• Check Trans “ON”.
• DTC stored.
• MIL request “ON”. (EURO 4 only)
Conditions For Clearing The DTC
•
The DTC can be cleared from the TCM history by
using a scan tool.
• The DTC will be cleared from history when the
vehicle has achieved 40 warm-up cycles without a
failure reported.
•
After more than 1 second has elapsed after the
ignition key has been turned “ON”, short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.
Diagnostic Aids
• Inspect the wiring for poor electrical connection at the
TCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring.
Inspect for a broken wire inside the insulation.
• W hen diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.

Circuit/System Testing DTC P0973 or P0974

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Start the engine.
3. Depress the brake pedal and place the select lever in D position.
4. Press the 3rd start switch. (Turn the 3rd start switch “ON”.)
5. Press the 3rd start switch again. (Turn the 3rd start switch “OFF”.)

Does a scan tool indicate DTC P0973 or P0974? — Go to
Step 3 Refer to
Diagnostic Aids
3 1. Turn “ON” the ignition with the engine “ON”.
2. Place the selector lever in the “P” position.
3. Measure the voltage between terminal C94-16 and terminal C94-1 (GND) on the TCM pigtail
connector by 5-8840-0285-0 DMM.

Is the voltage specified value? 8∼16V Go to
Step 4 Go to Step 10

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-97

DTC P0976 or P0977 (Flash Code 32)




RTW 77ALF001501

Circuit Description
The shift solenoid S2 changes the hydraulic route with
the signals from the TCM according to the vehicle
speed and the throttle opening to control shifting. W hen
the shift solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.
Condition For Running The DTC
All of the following conditions are met.
(1) All of the following conditions are met for 2 seconds or more continuously.
• The supply voltage is more than 10.2 volts and
less than 15.5 volts.
(2) Not emergency mode.
(3) 0.025 seconds or more passed after the state o
f
power “ON” solenoid is changed.
(4) All of the following conditions are met. • Device Control is not operating.
• Disable Normal Communication is receiving
enable.
• DTC Clear is not operating.



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ISUZU KB P190 2007

7A2-98 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P0976)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P0977)
Action Taken When The DTC Sets
• No L-up control.
• No line pressure reduction control at gear change.
• No torque reduction control.
• No squat control.
• No slope control (keep mode).
• No line pressure reduction control at garage.
• No input revolution sensor failure detection.
• No shift solenoid failure detection.
• No L-up solenoid failure detection.
• Change to emergency mode.
• Check Trans “ON”.
• DTC stored.
• MIL request “ON”. (EURO 4 only)
Conditions For Clearing The DTC
•
The DTC can be cleared from the TCM history by
using a scan tool.
• The DTC will be cleared from history when the vehicle has achieved 40 warm-up cycles without a
failure reported.
•
After more than 1 second has elapsed after the
ignition key has been turned “ON”, short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.
Diagnostic Aids
• Inspect the wiring for poor electrical connection at the
TCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring.
Inspect for a broken wire inside the insulation.
• W hen diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.

Circuit/System Testing DTC P0976 or P0977

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Start the engine.
3. Depress the brake pedal and place the select lever in D position.
4. Press the 3rd start switch. (Turn the 3rd start switch “ON”.)
5. Press the 3rd start switch again. (Turn the 3rd start switch “OFF”.)

Does a scan tool indicate DTC P0976 or P0977? — Go to
Step 3 Refer to
Diagnostic Aids
3 1. Turn “ON” the ignition with the engine “ON”.
2. Place the selector lever in the “P” position.
3. Measure the voltage between terminal C94-15 and terminal C94-1 on the TCM pigtail connector by 5-
8840-0285-0 DMM.

Is the voltage specified value? 8∼16V Go to
Step 4 Go to Step 5

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ISUZU KB P190 2007

7A2-102 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Circuit/System Testing DTC P1790

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Turn “OFF” the ignition and keep the position for
more than 30 seconds.
3. Turn “ON” the ignition.
4. Check the DTC on a scan tool.

Does a scan tool indicate DTC P1791? — Go to
Step 3 Refer to
Diagnostic Aids
3 Perform the SPS for the TCM.
Is the action complete? — Go to
Step 4 —
4 Recheck the DTC on the scan tool.

Does the scan tool indicate DTC P1790? — Go to
Step 5 Go to Step 6
5 Replace the TCM.
Important: The replacement TCM must be
programmed (Refer to SPS for procedure).

Is the action complete? — Go to
Step 6 —
6 1. Reconnect all previously disconnected harness
connector(s).
2. Clear the DTCs with a scan tool.
3. Turn “OFF” the ignition.
4. Start the engine.
5. Operate the vehicle within the Conditions For Running the DTC. You may also operate the
vehicle within the conditions that you observed
from the Freeze Frame/ Failure Records.

Did the DTC fail this ignition? —
Go to Step 2 Go to Step 7
7 Observe the stored information, Capture info with a
scan tool.

Are there any DTCs that you have not diagnosed? —
Go to
Diagnostic
Trouble Code (DTC) List Verify repair


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ISUZU KB P190 2007

7A2-104 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Circuit/System Testing DTC P1791

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Turn “OFF” the ignition and keep the position for
more than 30 seconds.
3. Turn “ON” the ignition.
4. Check the DTC on the scan tool.

Does a scan tool indicate DTC P1791? — Go to
Step 3 Refer to
Diagnostic Aids
3 Replace the TCM.
Important: The replacement TCM must be
programmed (Refer to SPS for procedure).

Is the action complete? — Go to
Step 4 —
4 1. Reconnect all previously disconnected harness
connector(s).
2. Clear the DTCs with a scan tool.
3. Turn “OFF” the ignition.
4. Start the engine.
5. Operate the vehicle within the Conditions For Running the DTC. You may also operate the
vehicle within the conditions that you observed
from the Freeze Frame/ Failure Records.

Did the DTC fail this ignition? —
Go to Step 2 Go to Step 5
5 Observe the stored information, Capture info with a
scan tool.

Are there any DTCs that you have not diagnosed? —
Go to
Diagnostic
Trouble Code (DTC) List Verify repair


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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-105

DTC P2769 or P2770 (Flash Code 33)




RTW 77ALF001501

Circuit Description
The lock-up solenoid SL of the torque converter clutch
(TCC) controls the lock-up clutch by a signal according
to the lock-up position judgment of the TCM when the
vehicle runs.
This function can improve the fuel consumption to
almost the same extent as the manual transmission.
The lock-up solenoid SL is put into B+ by the TCM, so
that the solenoid is actuated with the result of lock-up.

Condition For Running The DTC
All of the following conditions are met.
(1) All of the following conditions are met for 2 seconds or more continuously.
• The supply voltage is more than 10.2 volts and
less than 15.5 volts.
(2) Not emergency mode.
(3) 0.025 seconds or more passed after the state o
f
energized solenoid is changed.


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ISUZU KB P190 2007

7A2-106 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

(4) All of the following conditions are met.
• Device Control is not operating.
• Disable Normal Communication is receiving enable.
• DTC Clear is not operating.
Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P2769)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P2770)
Action Taken When The DTC Sets
• No L-up solenoid functional failure detection.
• No squat control. (DTC P2770)
• The TCM fixes to 1st gear when the vehicle speed is less than 10 km/h (6 mph).
• Check Trans “ON”.
• DTC stored.
• MIL request “ON”. (EURO 4 only)
Conditions For Clearing The DTC
•
The DTC can be cleared from the TCM history by
using a scan tool.
• The DTC will be cleared from history when the vehicle has achieved 40 warm-up cycles without a
failure reported.
•
After more than 1 second has elapsed after the
ignition key has been turned “ON”, short between
No.11 and No.5 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.
Diagnostic Aids
• Inspect the wiring for poor electrical connection at the
TCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring. Inspect for a
broken wire inside the insulation.
• W hen diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.
Circuit/System Testing DTC P2769 or P2770

Step Action Value(s) YES NO
1
W as the On-Board Diagnostic (OBD) System Check
performed? — Go to
Step 2 Go to OBD
System Check
2 1. Install a scan tool.
2. Start the engine.
3. Drive the vehicle in D position.
4. Accelerate the vehicle until the gear position
becomes the 4th.
5. Release the accelerator pedal and accelerate the vehicle until the gear position becomes the 4th
again.

Does a scan tool indicate DTC P2769 or P2770? — Go to
Step 3 Refer to
Diagnostic Aids

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ISUZU KB P190 2007